sqashing bigrams

perl -pwe 's/the/A/g; s/in/B/g; s/re/C/g; s/that/D/g; s/on/E/g; s/an/F/g; s/er/G/g; s/ou/H/g; s/it/I/g; s/en/J/g; s/st/K/g; s/or/L/g; s/Bg/M/g; s/al/N/g; s/at/O/g; s/to/P/g; s/is/Q/g; s/as/R/g; s/ar/S/g; s/le/T/g; s/ed/U/g; s/th/V/g; s/es/W/g; s/of/X/g; s/ic/Y/g; s/ly/Z/g'

#! perl -pw s/\Q th/A/g; s/\Qe /B/g; s/\Qt /C/g; s/\Qs /D/g; s/\Qin/E/g; s/\Qer/F/g; s/\Q a/G/g; s/\Qon/H/g; s/\Qd /I/g; s/\QAB/J/g; s/\Qto /K/g; s/\Qy /L/g; s/\Qen/M/g; s/\Qou/N/g; s/\QEg /O/g; s/\Qor/P/g; s/\Q. /Q/g; s/\Qan/R/g; s/\Qre/S/g; s/\Q, /T/g; s/\Qat/U/g; s/\Qit/V/g; s/\Qal/W/g; s/\Qar/X/g; s/\QAaC/Y/g; s/\Qst/Z/g;

Is greedy suboptimal?